The X1x Rectangle Shelf fits perfectly on your X1x trade show pop-up display frame. Also, it offers a great space to showcase your product or literature. Note: If you are purchasing or already own a 4×3 frame, the X1x Rectangle Shelf size is a little smaller. Please note in your order or call to confirm you get the correct shelf. If ordering a 4×3 frame at the same time, we will automatically adjust the shelf for that frame size.